AMHERST – As another semester begins, fire officials still do not know the cause of a fire in January that killed a University of Massachusetts senior about to enter his final term.

Investigators are also unwilling to yet say they won’t ever know the cause of the Jan. 21 blaze that killed James "Jake" Hoffman.

“There is a great hope it will be solved,” said Jennifer Mieth, spokeswoman for the state fire marshal’s office.

Hoffman, a 21-year-old senior in the Isenberg School's Department of Tourism Management, died in the fire at the Rolling Green apartments located off Route 9. More than 30 people were displaced from the 10-unit complex, including 22 UMass students.

“Each investigation takes its own time. The more quickly you can solve it the better off you off,” Mieth said.

And some are easier. Firefighters knew within days, for instance, that the July fire at Brunelle’s Marina in South Hadley was caused by a failure in the electrical system at the Dockside restaurant.

Mieth said once investigators can isolate where the fire began, “then they begin to systematically eliminate all possible causes.”

For this fire at Rolling Green, they are waiting forensic results, according to Mieth. There has been a slow down in work at the state lab, especially in the wake of the Boston Marathon bombings and related forensics needed for that case.

“There’s only so many resources,” she said. She said her heart goes out to Hoffman’s family who are waiting for answers. Despite not knowing now, she said, investigators in the Amherst fire are not ready to say the don’t or won’t ever know the cause.

Amherst Fire Chief Tim Nelson said the state has taken over the investigation, and his department is also awaiting the results. “It does take time,”the chief said.

Nelson said it is important the state investigators fully analyze the data and get the cause right.

The fire began in the apartment in which Hoffman lived, and he died from smoke inhalation, according to reports at the time of the blaze.

The 10 damaged units, meanwhile, are being renovated. The buildings have been cleared to the studs, Nelson said, and a new roof is up. “They’re going to put in a new sprinkler system, which for us is huge,” he said.

Nelson said the management company for the apartments had been hoping to have the units ready for fall occupancy.

The building is owned and managed by the Chicago-based Equity Residential. A spokesman for that company could not be reached for comment.